/**
* Copyright (C) 2008 Happy Fish / YuQing
*
* FastDFS Java Client may be copied only under the terms of the GNU Lesser
* General Public License (LGPL).
* Please visit the FastDFS Home Page http://www.csource.org/ for more detail.
*/

package org.csource.fastdfs;

import java.io.IOException;
import java.lang.reflect.Array;

/**
* C struct body decoder
* @author Happy Fish / YuQing
* @version Version 1.17
*/
public class ProtoStructDecoder<T extends StructBase>
{	
/**
* Constructor
*/
	public ProtoStructDecoder()
	{
	}
	
/**
* decode byte buffer
*/
	@SuppressWarnings("unchecked")
	public T[] decode(byte[] bs, Class<T> clazz, int fieldsTotalSize) throws Exception
	{
		if (bs.length % fieldsTotalSize != 0)
		{
			throw new IOException("byte array length: " + bs.length + " is invalid!");
		}
		
		int count = bs.length / fieldsTotalSize;
		int offset;
		T[] results = (T[])Array.newInstance(clazz, count);
		
		offset = 0;
		for (int i=0; i<results.length; i++)
		{
			results[i] = clazz.newInstance();
			results[i].setFields(bs, offset);
			offset += fieldsTotalSize;
		}
		
		return results;
	}
}
